packages/utilities/fast-colors/src/color-lch.ts
import { roundToPrecisionSmall } from "./math-utilities.js";
/**
*
* {@link https://en.wikipedia.org/wiki/CIELAB_color_space | CIELCH color space}
*
* This is a cylindrical representation of the CIELAB space useful for saturation operations
* This uses Hue values in "degree" format. So expect a range of [0,360]. Some other implementations instead uses radians or a normalized Hue with range [0,1]. Be aware of this when checking values or using other libraries.
* This implementation uses the D65 constants for 2 degrees. That determines the constants used for the pure white point of the XYZ space of 0.95047, 1.0, 1.08883.
* {@link https://en.wikipedia.org/wiki/Illuminant_D65}
* These constants determine how the XYZ, LCH and LAB colors convert to/from RGB.
*
* @public
*/
export class ColorLCH {
/**
* Construct a {@link ColorLCH} from a config object.
* @param data - the config object
*/
public static fromObject(data: { l: number; c: number; h: number }): ColorLCH | null {
if (data && !isNaN(data.l) && !isNaN(data.c) && !isNaN(data.h)) {
return new ColorLCH(data.l, data.c, data.h);
}
return null;
}
constructor(l: number, c: number, h: number) {
this.l = l;
this.c = c;
this.h = h;
}
public readonly l: number;
public readonly c: number;
public readonly h: number;
/**
* Determines if one color is equal to another.
* @param rhs - the color to compare
*/
public equalValue(rhs: ColorLCH): boolean {
return this.l === rhs.l && this.c === rhs.c && this.h === rhs.h;
}
/**
* Returns a new {@link ColorLCH} rounded to the provided precision
* @param precision - the precision to round to
*/
public roundToPrecision(precision: number): ColorLCH {
return new ColorLCH(
roundToPrecisionSmall(this.l, precision),
roundToPrecisionSmall(this.c, precision),
roundToPrecisionSmall(this.h, precision)
);
}
/**
* Converts the {@link ColorLCH} to a config object.
*/
public toObject(): { l: number; c: number; h: number } {
return { l: this.l, c: this.c, h: this.h };
}
}